The present inventors have recognized that typical in-counter and presentation-type data readers do not use solid state imaging devices, such as a charge-coupled device (CCD) imager or a complimentary metal-oxide-semiconductor (CMOS) imager to capture data. The present inventors have also recognized there are several challenges to including solid state imaging devices in in-counter and presentation-style data readers. One such challenge is locating a light source in the housing such that a read volume is adequately illuminated without reflecting light back onto the solid state imager. Another such challenge recognized by the present inventors is providing a light source including light emitting diodes (LEDs) that does not create harsh point source lighting effects, such as shining brightly in a user's eyes. Another such challenge is providing a light source including LEDs that lights a read volume relatively evenly and without creating specular reflection off an object in the read volume.
One device for using LEDs as a light source for a bar code reader includes a number of conical reflectors with an LED at the base of each cone as disclosed in U.S. Pat. No. 5,723,868. While rotationally symmetric reflectors, such as cylindrical reflective cones, are efficient at reflecting light emitted from each LED, the present inventors have recognized that such rotationally symmetric reflectors produce a circular appearance of light and do not blend the light from each LED together, thus creating brighter and darker areas in the illuminated area and an unpleasing appearance.
Accordingly, the present inventors recognized there is a need for an in-counter, presentation-style, or other suitable style, data reader with a solid state imager and a lighting system with lighting devices that provide adequate illumination for the solid state imager to capture high-quality images of objects in a read volume. The present inventors also recognized there is a need for a lighting system with improved lighting devices that (a) do not reflect light onto the solid state imager, (b) do not create harsh point source lighting effects, (c) lights a read volume relatively evenly, (d) does not create specular reflection off an object in the read volume, and (e) blends the light from multiple LEDs together to create illumination without substantially brighter and darker areas, singularly, or in any combination.